Correlation between adrenal central vein parasitism and heart fibrosis in chronic chagasic myocarditis

The correlation between Trypanosoma cruzi parasitism of the adrenal central vein (ACV) wall and fibrous connective tissue neoformation in the left ventricular myocardium (LVM) of patients with chronic Chagas' disease who were autopsied was evaluated using the following procedures: 1) a comparison of the incidence of fibrosis in the LVM among 18 chagasic patients with ACV parasitism and 18 individuals without phleboparasitism; 2) a determination of fibrosis intensity in the LVM in 12 cases with ACV parasites and in 12 cases without phleboparasitism, matched with respect to age, sex, race, and anatomoclinical form of the disease (indeterminant, cardiac, and digestive forms); and 3) in the cases with ACV parasitism, a calculation of Pearson's correlation coefficient between T. cruzi nests in the vessel and the intensity of fibrous connective tissue neoformation in the LVM. Among chagasic individuals with adrenal phleboparasitism, there was an increased incidence and intensity of fibrous connective tissue neoformation in the LVM, both highly significant, compared with patients without adrenal phleboparasitism. Furthermore, there was a positive, though nonsignificant, correlation (r = +0.19) between the density of nests in the ACV and the intensity of myocardial fibrosis. These results are consistent with previous data showing a higher intensity of the leukocyte exudate in the LVM and increased heart weight in individuals with T. cruzi nests in the ACV, suggesting a role of parasitism at that site in terms of the development of chronic chagasic cardiopathy.